Transactions on Electrical and Electronic Materials

  • 제9권3호
  • /
  • Pages.105-109
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  • 2008
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  • 1229-7607(pISSN)
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  • 2092-7592(eISSN)
한국전기전자재료학회 (The Korean Institute of Electrical and Electronic Material Engineers)
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Electrical Characteristics of Organic Light-emitting Diodes Fabricated by Varying a Hole-size in Evaporation Boat

  • Kim, Weon-Jong (Department of Electrical Engineering, Kwangwoon University) ;
  • Park, Young-Ha (Department of Electrical Engineering, Kwangwoon University) ;
  • Cho, Kyung-Soon (Department of Electrical Engineering, Kwangwoon University) ;
  • Hong, Jin-Woong (Department of Electrical Engineering, Kwangwoon University) ;
  • Shin, Jong-Yeol (Department of Car Mechatronics, Sahmyook University) ;
  • Kim, Tae-Wan (Department of Physics, Hongik University)
  • 발행 : 2008.06.30
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초록

Electrical characteristics of organic light-emitting diodes were investigated by varying a hole-size in evaporation boat in the device structure of ITO/tris(8-hydroxyquinoline) aluminum$(Alq_3)$/Al. The device was manufactured using a thermal evaporation under a base pressure of $5{\times}10^{-6}$ Torr. The $Alq_3$ emitting organics were evaporated to be a thickness of 100 nm at a deposition rate of $1.5{\AA}/s$. A cylindrical-shaped evaporation boat was made out of stainless steel with a small size of hole on top of the boat. Several evaporation boats were made having a different hole size on top; 0.8 mm, 1.0 mm, 1.5 mm, and 3.0 mm. We found that when the hole size on top of the evaporation boat is 1.0 mm, the average roughness is rather smoother compared to the other ones. Also, luminance and external quantum efficiency are superior to the others. Compared to the ones from the devices made with the hole-size of 0.8 mm boat. The luminance and external quantum efficiency of the device made with the hole-size of 1.0 mm boat were improved by a factor of seventy and thirty three, respectively. Also operating voltage is reduced to 2 V.

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참고문헌

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